package com.itheima.controller;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.itheima.bean.ShoppingCart;
import com.itheima.commons.BaseContext;
import com.itheima.commons.R;
import com.itheima.exception.CustomException;
import com.itheima.service.ShoppingCartService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.time.LocalDateTime;
import java.util.List;

/**
 * @author Tang
 * @date 2023/1/12
 */
@Slf4j
@RequestMapping("/shoppingCart")
@RestController
public class ShoppingCartController {
    @Autowired
    private ShoppingCartService shoppingCartService;

    /**
     * 添加购物车
     *
     * @param shoppingCart
     * @return
     */
    @PostMapping("/add")
    public R<ShoppingCart> addShoppingCart(@RequestBody ShoppingCart shoppingCart) {
        //0. 获取当前登录用户的id
        Long userId = BaseContext.getCurrentId();

        if (shoppingCart == null) {
            throw new CustomException("请先选择商品添加到购物车！");
        }

        //1. 判断当前购物车中是否存在该商品  唯一的判断  eg：添加第一条数据---辣椒炒肉：口味信息 微辣  又添加一条辣椒炒肉，口味信息：重辣
        LambdaQueryWrapper<ShoppingCart> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.eq(ShoppingCart::getUserId, userId);
        if (shoppingCart.getDishId() != null) {  //如果是添加菜品
            queryWrapper.eq(ShoppingCart::getDishId, shoppingCart.getDishId());
            queryWrapper.eq(shoppingCart.getDishFlavor() != null, ShoppingCart::getDishFlavor, shoppingCart.getDishFlavor());
        } else {                                //添加套餐
            queryWrapper.eq(ShoppingCart::getSetmealId, shoppingCart.getSetmealId());
        }
        ShoppingCart cart = shoppingCartService.getOne(queryWrapper);

        //2. 如果存在该商品，直接number数量+1
        if (cart != null) {
            cart.setNumber(cart.getNumber() + 1);
        } else {
            //3. 如果不存在该商品，需要补齐一些字段：user_id、number、crate_time
            cart = shoppingCart;
            cart.setNumber(1);  //添加商品默认数量为1
            cart.setUserId(userId); //关联用户id
            cart.setCreateTime(LocalDateTime.now());
        }

        //4. 调用service保存购物车数据  这里使用saveOrUpdate  新增或更新
        shoppingCartService.saveOrUpdate(cart);

        //5. 返回结果
        return R.success(cart);
    }

    /**
     * 查询购物车
     *
     * @return
     */
    @GetMapping("/list")
    public R<List<ShoppingCart>> list() {
        //【特别注意】需要查询的是当前用户的购物车数据
        //1.获取当前登录用户的id
        Long userId = BaseContext.getCurrentId();
        if (userId == null) {
            throw new CustomException("该用户不存在！");
        }
        //2.根据当前用户id查询购物车
        LambdaQueryWrapper<ShoppingCart> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.eq(ShoppingCart::getUserId, userId);
        List<ShoppingCart> list = shoppingCartService.list(queryWrapper);

        //3.返回结果
        return R.success(list);
    }

    /**
     * 清空购物车
     *
     * @return
     */
    @DeleteMapping("/clean")
    public R<String> clean() {
        //1.获取当前登录用户的id
        Long userId = BaseContext.getCurrentId();
        if (userId == null) {
            throw new CustomException("该用户不存在！");
        }

        //2.根据当前用户id清空购物车，调用service删除方法
        LambdaQueryWrapper<ShoppingCart> wrapper = new LambdaQueryWrapper<>();
        wrapper.eq(ShoppingCart::getUserId, userId);
        boolean flag = shoppingCartService.remove(wrapper);

        //3.返回结果
        return flag ? R.success("清空购物车成功！") : R.error("清空购物车失败！");
    }

    //购物车sub操作
    @PostMapping("/sub")
    public R<ShoppingCart> sub(@RequestBody ShoppingCart shoppingCart){
        Long currentId = BaseContext.getCurrentId();
        LambdaQueryWrapper<ShoppingCart> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.eq(ShoppingCart::getUserId, currentId);
        ShoppingCart cart = null;

        // 获取要减少的菜品或套餐信息
        Long dishId = shoppingCart.getDishId();
        if(dishId == null){
            // 减少的是套餐数量
            Long setmealId = shoppingCart.getSetmealId();
            queryWrapper.eq(ShoppingCart::getSetmealId, setmealId);
            cart = shoppingCartService.getOne(queryWrapper);
        } else {
            // 减少的是菜品数量
            queryWrapper.eq(ShoppingCart::getDishId, dishId);
            cart = shoppingCartService.getOne(queryWrapper);
        }

        Integer number = cart.getNumber();
        if(number > 1){
            cart.setNumber(number - 1);
            shoppingCartService.updateById(cart);
        } else {
            shoppingCartService.removeById(cart.getId());
        }

        return R.success(cart);
    }

   // @PostMapping("/add")
   // public R<ShoppingCart>add(@RequestBody )


}
